@speakingwoman fascinating question- I don't see why it matters...
I'm female, and I have given birth. I've breastfed. I've been a stay home Mum.
Anecdotal evidence is not data.
Ops question weighed heavily on me for years, especially with its implications around Trans issues (don't want to derail thread here). And so I did a LOT of reading and have come out the other side feeling that if you assume more similarity than divergence between the sexes people and life make a lot more sense.
And really, the science is quite clear. Some divergence, a lot of it fairly superficial (some anatomical difference- remember all fetuses start female, sexual organs are equivalent- ie clitorus and penis are corresponding organ), brains show very little divergence. It's somewhat like racial divergence. People with more Chinese genetic material are likely to be smaller- people with African material darker skin. People on a western diet are more likely to be big... doesn't mean any of them are innately better at parenting.
Re testosterone. It's about sensitivity. Let's say my husband makes loads but his receptors are few. Let's say I make a little but have great receptors. The net effect is he will display fewer traits associated with T, and I will display more. I still have female sex organs- he still has his trouser snake, but in many ways I would conform to a more male set of behaviours and he may be more nuturing.
Post menopausal women often have far more testosterone than their husbands. It's a good explanation for why often men of that age want to nest while the women want to explore. The point is, biological sex changes with age, external factors such as diet and environment and so on.
Yes hormones carry innate behavioural instructions, but the thing you have in your pants doesn't necessarily tell you how those hormones work for you in your particular body.
However, society looks at what you have in your pants and tells you every day from birth how you should think, feel, behave without taking into account the fact that your junk isn't the whole story.